I am a sound design student. I am exploring the subject of history of sound formats, especially Split Surround. Unfortunately, there is not enough information for me to understand this concept. I thought it is a good idea to ask this question here. While researching I found an article that confused me even more:
"Split Surround was compatible with the Baby Boom format. Like Baby Boom, Split Surround had the same left, center, right, mono surround, and two boom tracks. The added left and right surrounds were put on the same tracks as the two boom tracks. This was accomplished by limiting the boom tracks to under 200 Hz and the left and right surrounds were limited to about 500 Hz."
Split Surround was the first 5.1 as we know it today (http://frank.mtsu.edu/~smpte/seventies.html) As far as I am aware 5.1 means 5 channels (left, center, right, left surround, right surround) + a sub-bass channel. Why then Split Surround used two boom channels? What is Mono Surround? What was the speakers setup of Split Surround?
I will be grateful for explaining me this abstruse concept. Many thanks in advance